Intermittent o/heating 96’ 2.5 turbo D

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Cuvner
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Intermittent o/heating 96’ 2.5 turbo D

Post by Cuvner » Mon Apr 22, 2019 4:54 pm

After a year of having a replacement head and removing the rear cooling pipe work the van is intermittently o/heating. At a loose end now and need to visit a good local specialist, live in Bournemouth Dorset, who should I see? Thanks in advance.
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Tony x
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by Tony x » Mon Apr 22, 2019 5:07 pm

You could try bleeding the cooling system (specialist knowledge needed but not hard) and then have ito pressure tested (most garages can do)
To answer your question this chap is highly regarded...

https://www.allansvehicleservices.co.uk/
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by g8dhe » Mon Apr 22, 2019 5:10 pm

If its intermittently overheating you may have a pin hole in a pipe which squirts coolant out under pressure and draws in air when it cools down until there is sufficient to cause an air-lock and overheat, check the pipes and get the garage to do so as well looking for any signs of a leak or use a UV dye to see if it can be spotted.
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by Ian » Mon Apr 22, 2019 6:01 pm

This firm are in Poole and come highly recommended: https://igmaynard.co.uk/blog/2016/08/05 ... ors-poole/
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by Bob » Mon Apr 22, 2019 6:50 pm

Good advice above, and whatever you do don't drive it until it's sorted.

You don't want to crack the head. :wink:
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by mikeonb4c » Mon Apr 22, 2019 9:13 pm

Did you have new radiators fitted, new thermostat, new temp sensor when the head was done? Poor performance on any of these could link to overheating
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by Tony x » Mon Apr 22, 2019 11:11 pm

mikeonb4c wrote: Mon Apr 22, 2019 9:13 pm Did you had new radiators fitted, new thermostat, new temp sensor when the head was done? Poor performance on any of these could link to overheating
...and new water pump.
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by Cuvner » Wed Apr 24, 2019 9:50 am

Thanks for all the replies, my dad had all the work done and I believe all parts had been replaced. I’ve just watched the videos on how to bleed the system properly so I will try that first. Thanks again
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by Cuvner » Wed Apr 24, 2019 11:33 pm

Quite a big update, so I’ve spent all night trying to get to the bottom of the intermittent o/h. I’m stating to think it’s terminal, the coolant system will pressurise after every bleed, makes lots of gargling sounds. Sometimes the hot air will work work sometimes not. Does this sound like a cracked head? There’s no performance loss or misfires. Don’t know what to do now apart from sell as spares. Any advice much appreciated
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by Ian » Thu Apr 25, 2019 10:31 am

This may help. It's from the "Overheating" fact sheet in the members area.

"If the water loss is more apparent during or after the vehicle has been on a run, this may signify that the water could is entering the cylinders of the engine due to head gasket or cylinder head failure. This is often noted by a hesitation to start in the morning, with a lumpy idle or a billowing of white smoke while being driven. If the failure is dramatic the vehicle resembles a steam engine and creates huge amounts of white smoke. However more often than not the loss is gradual and more difficult to detect.

The best way to prove the theory is by taking the vehicle on a 30-minute run and parking it up for the night. When the engine has cooled enough to work on, remove the glowplug rail and all four glowplugs from the cylinders. In the morning, return to the vehicle and place a strip of card some 9” by 20” (20 x 40cm) across the top of the glowplug holes and turn the engine over. the glowplug holes act as vents and anything in the cylinder will be forced up through them rather than down the valves. With any luck you will have three black carbon styles ‘splots’ and a larger watery splot where water has collected in the cylinder overnight. (Note, it is possible to have failure in more than one cylinder.)"
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by mikeonb4c » Thu Apr 25, 2019 11:17 am

Cuvner wrote: Wed Apr 24, 2019 11:33 pm Quite a big update, so I’ve spent all night trying to get to the bottom of the intermittent o/h. I’m stating to think it’s terminal, the coolant system will pressurise after every bleed, makes lots of gargling sounds. Sometimes the hot air will work work sometimes not. Does this sound like a cracked head? There’s no performance loss or misfires. Don’t know what to do now apart from sell as spares. Any advice much appreciated
Very unfortunate that, after everything was replaced. Was the replacement head and gasket from a good source and fitted by an experienced Bongo mechanic?
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Re: Intermittent o/heating 96’ 2.5 turbo D

Post by Tony x » Thu Apr 25, 2019 10:08 pm

One further test would be to test the coolant for exhaust gasses. Not 100% conclusive in that it can show all is OK when it is not but maybe worth a go.
Personally I'd put a new thermostat in there just in case a none Mazda one was used and is failing to open.
Sorry to say I'm not that optimistic given what you've said so far but it is still possible your head is OK
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